diff --git a/MQTTConnection.h b/MQTTConnection.h
index ecd8143..9f718da 100644
--- a/MQTTConnection.h
+++ b/MQTTConnection.h
@@ -1,5 +1,5 @@
 /*
- *   Copyright (C) 2022,2023 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2022,2023,2025 by Jonathan Naylor G4KLX
  *
  *   This program is free software; you can redistribute it and/or modify
  *   it under the terms of the GNU General Public License as published by
@@ -24,10 +24,10 @@
 #include <vector>
 #include <string>
 
-enum class MQTT_QOS {
-	AT_MODE_ONCE  = 0U,
-	AT_LEAST_ONCE = 1U,
-	EXACTLY_ONCE  = 2U
+enum class MQTT_QOS : int {
+	AT_MODE_ONCE  = 0,
+	AT_LEAST_ONCE = 1,
+	EXACTLY_ONCE  = 2
 };
 
 class CMQTTConnection {